/* eggaccelerators.c
 * Copyright (C) 2002  Red Hat, Inc.; Copyright 1998, 2001 Tim Janik
 * Developed by Havoc Pennington, Tim Janik
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Library General Public
 * License as published by the Free Software Foundation; either
 * version 2 of the License, or (at your option) any later version.
 *
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Library General Public License for more details.
 *
 * You should have received a copy of the GNU Library General Public
 * License along with this library; if not, write to the
 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
 * Boston, MA 02111-1307, USA.
 */

#include "eggaccelerators.h"

#include <stdlib.h>
#include <string.h>
#include <gdkconfig.h>
#ifdef GDK_WINDOWING_X11
#include <gdk/gdkx.h>
#endif
#include <gdk/gdkkeysyms.h>

enum {
    EGG_MODMAP_ENTRY_SHIFT = 0,
    EGG_MODMAP_ENTRY_LOCK = 1,
    EGG_MODMAP_ENTRY_CONTROL = 2,
    EGG_MODMAP_ENTRY_MOD1 = 3,
    EGG_MODMAP_ENTRY_MOD2 = 4,
    EGG_MODMAP_ENTRY_MOD3 = 5,
    EGG_MODMAP_ENTRY_MOD4 = 6,
    EGG_MODMAP_ENTRY_MOD5 = 7,
    EGG_MODMAP_ENTRY_LAST = 8
};

#define MODMAP_ENTRY_TO_MODIFIER(x) (1 << (x))

typedef struct {
    EggVirtualModifierType mapping[EGG_MODMAP_ENTRY_LAST];

} EggModmap;

static const EggModmap* egg_keymap_get_modmap(GdkKeymap *keymap);

static inline gboolean
is_alt(const gchar *string) {
    return ((string[0] == '<') &&
            (string[1] == 'a' || string[1] == 'A') &&
            (string[2] == 'l' || string[2] == 'L') &&
            (string[3] == 't' || string[3] == 'T') &&
            (string[4] == '>'));
}

static inline gboolean
is_ctl(const gchar *string) {
    return ((string[0] == '<') &&
            (string[1] == 'c' || string[1] == 'C') &&
            (string[2] == 't' || string[2] == 'T') &&
            (string[3] == 'l' || string[3] == 'L') &&
            (string[4] == '>'));
}

static inline gboolean
is_modx(const gchar *string) {
    return ((string[0] == '<') &&
            (string[1] == 'm' || string[1] == 'M') &&
            (string[2] == 'o' || string[2] == 'O') &&
            (string[3] == 'd' || string[3] == 'D') &&
            (string[4] >= '1' && string[4] <= '5') &&
            (string[5] == '>'));
}

static inline gboolean
is_ctrl(const gchar *string) {
    return ((string[0] == '<') &&
            (string[1] == 'c' || string[1] == 'C') &&
            (string[2] == 't' || string[2] == 'T') &&
            (string[3] == 'r' || string[3] == 'R') &&
            (string[4] == 'l' || string[4] == 'L') &&
            (string[5] == '>'));
}

static inline gboolean
is_shft(const gchar *string) {
    return ((string[0] == '<') &&
            (string[1] == 's' || string[1] == 'S') &&
            (string[2] == 'h' || string[2] == 'H') &&
            (string[3] == 'f' || string[3] == 'F') &&
            (string[4] == 't' || string[4] == 'T') &&
            (string[5] == '>'));
}

static inline gboolean
is_shift(const gchar *string) {
    return ((string[0] == '<') &&
            (string[1] == 's' || string[1] == 'S') &&
            (string[2] == 'h' || string[2] == 'H') &&
            (string[3] == 'i' || string[3] == 'I') &&
            (string[4] == 'f' || string[4] == 'F') &&
            (string[5] == 't' || string[5] == 'T') &&
            (string[6] == '>'));
}

static inline gboolean
is_control(const gchar *string) {
    return ((string[0] == '<') &&
            (string[1] == 'c' || string[1] == 'C') &&
            (string[2] == 'o' || string[2] == 'O') &&
            (string[3] == 'n' || string[3] == 'N') &&
            (string[4] == 't' || string[4] == 'T') &&
            (string[5] == 'r' || string[5] == 'R') &&
            (string[6] == 'o' || string[6] == 'O') &&
            (string[7] == 'l' || string[7] == 'L') &&
            (string[8] == '>'));
}

static inline gboolean
is_release(const gchar *string) {
    return ((string[0] == '<') &&
            (string[1] == 'r' || string[1] == 'R') &&
            (string[2] == 'e' || string[2] == 'E') &&
            (string[3] == 'l' || string[3] == 'L') &&
            (string[4] == 'e' || string[4] == 'E') &&
            (string[5] == 'a' || string[5] == 'A') &&
            (string[6] == 's' || string[6] == 'S') &&
            (string[7] == 'e' || string[7] == 'E') &&
            (string[8] == '>'));
}

static inline gboolean
is_meta(const gchar *string) {
    return ((string[0] == '<') &&
            (string[1] == 'm' || string[1] == 'M') &&
            (string[2] == 'e' || string[2] == 'E') &&
            (string[3] == 't' || string[3] == 'T') &&
            (string[4] == 'a' || string[4] == 'A') &&
            (string[5] == '>'));
}

static inline gboolean
is_super(const gchar *string) {
    return ((string[0] == '<') &&
            (string[1] == 's' || string[1] == 'S') &&
            (string[2] == 'u' || string[2] == 'U') &&
            (string[3] == 'p' || string[3] == 'P') &&
            (string[4] == 'e' || string[4] == 'E') &&
            (string[5] == 'r' || string[5] == 'R') &&
            (string[6] == '>'));
}

static inline gboolean
is_hyper(const gchar *string) {
    return ((string[0] == '<') &&
            (string[1] == 'h' || string[1] == 'H') &&
            (string[2] == 'y' || string[2] == 'Y') &&
            (string[3] == 'p' || string[3] == 'P') &&
            (string[4] == 'e' || string[4] == 'E') &&
            (string[5] == 'r' || string[5] == 'R') &&
            (string[6] == '>'));
}

static inline gboolean
is_keycode(const gchar *string) {
    return ((string[0] == '0') &&
            (string[1] == 'x'));
}

/**
 * egg_accelerator_parse_virtual:
 * @accelerator:      string representing an accelerator
 * @accelerator_key:  return location for accelerator keyval
 * @accelerator_mods: return location for accelerator modifier mask
 *
 * Parses a string representing a virtual accelerator. The format
 * looks like "&lt;Control&gt;a" or "&lt;Shift&gt;&lt;Alt&gt;F1" or
 * "&lt;Release&gt;z" (the last one is for key release).  The parser
 * is fairly liberal and allows lower or upper case, and also
 * abbreviations such as "&lt;Ctl&gt;" and "&lt;Ctrl&gt;".
 *
 * If the parse fails, @accelerator_key and @accelerator_mods will
 * be set to 0 (zero) and %FALSE will be returned. If the string contains
 * only modifiers, @accelerator_key will be set to 0 but %TRUE will be
 * returned.
 *
 * The virtual vs. concrete accelerator distinction is a relic of
 * how the X Window System works; there are modifiers Mod2-Mod5 that
 * can represent various keyboard keys (numlock, meta, hyper, etc.),
 * the virtual modifier represents the keyboard key, the concrete
 * modifier the actual Mod2-Mod5 bits in the key press event.
 *
 * Returns: %TRUE on success.
 */
gboolean
egg_accelerator_parse_virtual(const gchar *accelerator,
        guint *accelerator_key,
        guint *keycode,
        EggVirtualModifierType *accelerator_mods) {
    guint keyval;
    GdkModifierType mods;
    gint len;
    gboolean bad_keyval;
    gint tmp_keycode;

    if (accelerator_key)
        *accelerator_key = 0;
    if (accelerator_mods)
        *accelerator_mods = 0;
    if (keycode)
        *keycode = 0;

    g_return_val_if_fail(accelerator != NULL, FALSE);

    bad_keyval = FALSE;
    tmp_keycode = 0;

    keyval = 0;
    mods = 0;
    len = strlen(accelerator);
    while (len) {
        if (*accelerator == '<') {
            if (len >= 9 && is_release(accelerator)) {
                accelerator += 9;
                len -= 9;
                mods |= EGG_VIRTUAL_RELEASE_MASK;
            } else if (len >= 9 && is_control(accelerator)) {
                accelerator += 9;
                len -= 9;
                mods |= EGG_VIRTUAL_CONTROL_MASK;
            } else if (len >= 7 && is_shift(accelerator)) {
                accelerator += 7;
                len -= 7;
                mods |= EGG_VIRTUAL_SHIFT_MASK;
            } else if (len >= 6 && is_shft(accelerator)) {
                accelerator += 6;
                len -= 6;
                mods |= EGG_VIRTUAL_SHIFT_MASK;
            } else if (len >= 6 && is_ctrl(accelerator)) {
                accelerator += 6;
                len -= 6;
                mods |= EGG_VIRTUAL_CONTROL_MASK;
            } else if (len >= 6 && is_modx(accelerator)) {
                static const guint mod_vals[] = {
                    EGG_VIRTUAL_ALT_MASK, EGG_VIRTUAL_MOD2_MASK, EGG_VIRTUAL_MOD3_MASK,
                    EGG_VIRTUAL_MOD4_MASK, EGG_VIRTUAL_MOD5_MASK
                };

                len -= 6;
                accelerator += 4;
                mods |= mod_vals[*accelerator - '1'];
                accelerator += 2;
            } else if (len >= 5 && is_ctl(accelerator)) {
                accelerator += 5;
                len -= 5;
                mods |= EGG_VIRTUAL_CONTROL_MASK;
            } else if (len >= 5 && is_alt(accelerator)) {
                accelerator += 5;
                len -= 5;
                mods |= EGG_VIRTUAL_ALT_MASK;
            } else if (len >= 6 && is_meta(accelerator)) {
                accelerator += 6;
                len -= 6;
                mods |= EGG_VIRTUAL_META_MASK;
            } else if (len >= 7 && is_hyper(accelerator)) {
                accelerator += 7;
                len -= 7;
                mods |= EGG_VIRTUAL_HYPER_MASK;
            } else if (len >= 7 && is_super(accelerator)) {
                accelerator += 7;
                len -= 7;
                mods |= EGG_VIRTUAL_SUPER_MASK;
            } else {
                gchar last_ch;

                last_ch = *accelerator;
                while (last_ch && last_ch != '>') {
                    last_ch = *accelerator;
                    accelerator += 1;
                    len -= 1;
                }
            }
        } else {
            keyval = gdk_keyval_from_name(accelerator);

            if (keyval == 0) {
                /* If keyval is 0, than maybe it's a keycode.  Check for 0x## */
                if (len >= 4 && is_keycode(accelerator)) {
                    char keystring[5];
                    gchar *endptr;

                    memcpy(keystring, accelerator, 4);
                    keystring [4] = '\000';

                    tmp_keycode = strtol(keystring, &endptr, 16);

                    if (endptr == NULL || *endptr != '\000') {
                        bad_keyval = TRUE;
                    } else {
                        /* 0x00 is an invalid keycode too. */
                        if (tmp_keycode == 0)
                            bad_keyval = TRUE;
                    }
                }
            }

            accelerator += len;
            len -= len;
        }
    }

    if (accelerator_key)
        *accelerator_key = gdk_keyval_to_lower(keyval);
    if (accelerator_mods)
        *accelerator_mods = mods;
    if (keycode)
        *keycode = tmp_keycode;

    return !bad_keyval;
}

/**
 * egg_virtual_accelerator_name:
 * @accelerator_key:  accelerator keyval
 * @accelerator_mods: accelerator modifier mask
 * @returns:          a newly-allocated accelerator name
 *
 * Converts an accelerator keyval and modifier mask
 * into a string parseable by egg_accelerator_parse_virtual().
 * For example, if you pass in #GDK_q and #EGG_VIRTUAL_CONTROL_MASK,
 * this function returns "&lt;Control&gt;q".
 *
 * The caller of this function must free the returned string.
 */
gchar*
egg_virtual_accelerator_name(guint accelerator_key,
        guint keycode,
        EggVirtualModifierType accelerator_mods) {
    static const gchar text_release[] = "<Release>";
    static const gchar text_shift[] = "<Shift>";
    static const gchar text_control[] = "<Control>";
    static const gchar text_mod1[] = "<Alt>";
    static const gchar text_mod2[] = "<Mod2>";
    static const gchar text_mod3[] = "<Mod3>";
    static const gchar text_mod4[] = "<Mod4>";
    static const gchar text_mod5[] = "<Mod5>";
    static const gchar text_meta[] = "<Meta>";
    static const gchar text_super[] = "<Super>";
    static const gchar text_hyper[] = "<Hyper>";
    guint l;
    gchar *keyval_name;
    gchar *accelerator;

    accelerator_mods &= EGG_VIRTUAL_MODIFIER_MASK;

    if (!accelerator_key) {
        keyval_name = g_strdup_printf("0x%02x", keycode);
    } else {
        keyval_name = gdk_keyval_name(gdk_keyval_to_lower(accelerator_key));
        if (!keyval_name)
            keyval_name = "";
    }

    l = 0;
    if (accelerator_mods & EGG_VIRTUAL_RELEASE_MASK)
        l += sizeof (text_release) - 1;
    if (accelerator_mods & EGG_VIRTUAL_SHIFT_MASK)
        l += sizeof (text_shift) - 1;
    if (accelerator_mods & EGG_VIRTUAL_CONTROL_MASK)
        l += sizeof (text_control) - 1;
    if (accelerator_mods & EGG_VIRTUAL_ALT_MASK)
        l += sizeof (text_mod1) - 1;
    if (accelerator_mods & EGG_VIRTUAL_MOD2_MASK)
        l += sizeof (text_mod2) - 1;
    if (accelerator_mods & EGG_VIRTUAL_MOD3_MASK)
        l += sizeof (text_mod3) - 1;
    if (accelerator_mods & EGG_VIRTUAL_MOD4_MASK)
        l += sizeof (text_mod4) - 1;
    if (accelerator_mods & EGG_VIRTUAL_MOD5_MASK)
        l += sizeof (text_mod5) - 1;
    if (accelerator_mods & EGG_VIRTUAL_META_MASK)
        l += sizeof (text_meta) - 1;
    if (accelerator_mods & EGG_VIRTUAL_HYPER_MASK)
        l += sizeof (text_hyper) - 1;
    if (accelerator_mods & EGG_VIRTUAL_SUPER_MASK)
        l += sizeof (text_super) - 1;
    l += strlen(keyval_name);

    accelerator = g_new(gchar, l + 1);

    l = 0;
    accelerator[l] = 0;
    if (accelerator_mods & EGG_VIRTUAL_RELEASE_MASK) {
        strcpy(accelerator + l, text_release);
        l += sizeof (text_release) - 1;
    }
    if (accelerator_mods & EGG_VIRTUAL_SHIFT_MASK) {
        strcpy(accelerator + l, text_shift);
        l += sizeof (text_shift) - 1;
    }
    if (accelerator_mods & EGG_VIRTUAL_CONTROL_MASK) {
        strcpy(accelerator + l, text_control);
        l += sizeof (text_control) - 1;
    }
    if (accelerator_mods & EGG_VIRTUAL_ALT_MASK) {
        strcpy(accelerator + l, text_mod1);
        l += sizeof (text_mod1) - 1;
    }
    if (accelerator_mods & EGG_VIRTUAL_MOD2_MASK) {
        strcpy(accelerator + l, text_mod2);
        l += sizeof (text_mod2) - 1;
    }
    if (accelerator_mods & EGG_VIRTUAL_MOD3_MASK) {
        strcpy(accelerator + l, text_mod3);
        l += sizeof (text_mod3) - 1;
    }
    if (accelerator_mods & EGG_VIRTUAL_MOD4_MASK) {
        strcpy(accelerator + l, text_mod4);
        l += sizeof (text_mod4) - 1;
    }
    if (accelerator_mods & EGG_VIRTUAL_MOD5_MASK) {
        strcpy(accelerator + l, text_mod5);
        l += sizeof (text_mod5) - 1;
    }
    if (accelerator_mods & EGG_VIRTUAL_META_MASK) {
        strcpy(accelerator + l, text_meta);
        l += sizeof (text_meta) - 1;
    }
    if (accelerator_mods & EGG_VIRTUAL_HYPER_MASK) {
        strcpy(accelerator + l, text_hyper);
        l += sizeof (text_hyper) - 1;
    }
    if (accelerator_mods & EGG_VIRTUAL_SUPER_MASK) {
        strcpy(accelerator + l, text_super);
        l += sizeof (text_super) - 1;
    }

    strcpy(accelerator + l, keyval_name);

    return accelerator;
}

void
egg_keymap_resolve_virtual_modifiers(GdkKeymap *keymap,
        EggVirtualModifierType virtual_mods,
        GdkModifierType *concrete_mods) {
    GdkModifierType concrete;
    int i;
    const EggModmap *modmap;

    g_return_if_fail(GDK_IS_KEYMAP(keymap));
    g_return_if_fail(concrete_mods != NULL);

    modmap = egg_keymap_get_modmap(keymap);

    /* Not so sure about this algorithm. */

    concrete = 0;
    i = 0;
    while (i < EGG_MODMAP_ENTRY_LAST) {
        if (modmap->mapping[i] & virtual_mods)
            concrete |= (1 << i);

        ++i;
    }

    *concrete_mods = concrete;
}

void
egg_keymap_virtualize_modifiers(GdkKeymap *keymap,
        GdkModifierType concrete_mods,
        EggVirtualModifierType *virtual_mods) {
    GdkModifierType virtual;
    int i;
    const EggModmap *modmap;

    g_return_if_fail(GDK_IS_KEYMAP(keymap));
    g_return_if_fail(virtual_mods != NULL);

    modmap = egg_keymap_get_modmap(keymap);

    /* Not so sure about this algorithm. */

    virtual = 0;
    i = 0;
    while (i < EGG_MODMAP_ENTRY_LAST) {
        if ((1 << i) & concrete_mods) {
            EggVirtualModifierType cleaned;

            cleaned = modmap->mapping[i] & ~(EGG_VIRTUAL_MOD2_MASK |
                    EGG_VIRTUAL_MOD3_MASK |
                    EGG_VIRTUAL_MOD4_MASK |
                    EGG_VIRTUAL_MOD5_MASK);

            if (cleaned != 0) {
                virtual |= cleaned;
            } else {
                /* Rather than dropping mod2->mod5 if not bound,
                 * go ahead and use the concrete names
                 */
                virtual |= modmap->mapping[i];
            }
        }

        ++i;
    }

    *virtual_mods = virtual;
}

static void
reload_modmap(GdkKeymap *keymap,
        EggModmap *modmap) {
#ifdef GDK_WINDOWING_X11
    XModifierKeymap *xmodmap;
    int map_size;
    int i;

    /* FIXME multihead */
    xmodmap = XGetModifierMapping(gdk_x11_get_default_xdisplay());

    memset(modmap->mapping, 0, sizeof (modmap->mapping));

    /* there are 8 modifiers, and the first 3 are shift, shift lock,
     * and control
     */
    map_size = 8 * xmodmap->max_keypermod;
    i = 3 * xmodmap->max_keypermod;
    while (i < map_size) {
        /* get the key code at this point in the map,
         * see if its keysym is one we're interested in
         */
        int keycode = xmodmap->modifiermap[i];
        GdkKeymapKey *keys;
        guint *keyvals;
        int n_entries;
        int j;
        EggVirtualModifierType mask;

        keys = NULL;
        keyvals = NULL;
        n_entries = 0;

        gdk_keymap_get_entries_for_keycode(keymap,
                keycode,
                &keys, &keyvals, &n_entries);

        mask = 0;
        j = 0;
        while (j < n_entries) {
            if (keyvals[j] == GDK_Num_Lock)
                mask |= EGG_VIRTUAL_NUM_LOCK_MASK;
            else if (keyvals[j] == GDK_Scroll_Lock)
                mask |= EGG_VIRTUAL_SCROLL_LOCK_MASK;
            else if (keyvals[j] == GDK_Meta_L ||
                    keyvals[j] == GDK_Meta_R)
                mask |= EGG_VIRTUAL_META_MASK;
            else if (keyvals[j] == GDK_Hyper_L ||
                    keyvals[j] == GDK_Hyper_R)
                mask |= EGG_VIRTUAL_HYPER_MASK;
            else if (keyvals[j] == GDK_Super_L ||
                    keyvals[j] == GDK_Super_R)
                mask |= EGG_VIRTUAL_SUPER_MASK;
            else if (keyvals[j] == GDK_Mode_switch)
                mask |= EGG_VIRTUAL_MODE_SWITCH_MASK;

            ++j;
        }

        /* Mod1Mask is 1 << 3 for example, i.e. the
         * fourth modifier, i / keyspermod is the modifier
         * index
         */
        modmap->mapping[i / xmodmap->max_keypermod] |= mask;

        g_free(keyvals);
        g_free(keys);

        ++i;
    }

    /* Add in the not-really-virtual fixed entries */
    modmap->mapping[EGG_MODMAP_ENTRY_SHIFT] |= EGG_VIRTUAL_SHIFT_MASK;
    modmap->mapping[EGG_MODMAP_ENTRY_CONTROL] |= EGG_VIRTUAL_CONTROL_MASK;
    modmap->mapping[EGG_MODMAP_ENTRY_LOCK] |= EGG_VIRTUAL_LOCK_MASK;
    modmap->mapping[EGG_MODMAP_ENTRY_MOD1] |= EGG_VIRTUAL_ALT_MASK;
    modmap->mapping[EGG_MODMAP_ENTRY_MOD2] |= EGG_VIRTUAL_MOD2_MASK;
    modmap->mapping[EGG_MODMAP_ENTRY_MOD3] |= EGG_VIRTUAL_MOD3_MASK;
    modmap->mapping[EGG_MODMAP_ENTRY_MOD4] |= EGG_VIRTUAL_MOD4_MASK;
    modmap->mapping[EGG_MODMAP_ENTRY_MOD5] |= EGG_VIRTUAL_MOD5_MASK;

    XFreeModifiermap(xmodmap);
#else
    g_error("Not yet implemented for Win32: eggaccelerators.c:reload_modmap()");
#endif
}

static const EggModmap*
egg_keymap_get_modmap(GdkKeymap *keymap) {
    EggModmap *modmap;

    /* This is all a hack, much simpler when we can just
     * modify GDK directly.
     */

    modmap = g_object_get_data(G_OBJECT(keymap),
            "egg-modmap");

    if (modmap == NULL) {
        modmap = g_new0(EggModmap, 1);

        /* FIXME modify keymap change events with an event filter
         * and force a reload if we get one
         */

        reload_modmap(keymap, modmap);

        g_object_set_data_full(G_OBJECT(keymap),
                "egg-modmap",
                modmap,
                g_free);
    }

    g_assert(modmap != NULL);

    return modmap;
}


